Bk your feed

![your_feed_updated](https://cloud.githubusercontent.com/assets/1451471/3247188/08df7602-f182-11e3-86b8-02d89fc7ea27.gif)
These should be testing that `userFeed.$activities` matches an actual element (i.e.: not just `jasmine.any($)`).

See [this comment](https://github.com/lonelyplanet/rizzo/pull/728#discussion_r13921746) for reference.